A sealing packer can be used to seal off portions of well casing when certain other sections are acidized. Commonly, a sealing packer can seal the upper portion of a well casing when the entire lower zone is acidized. Furthermore, sealing packers have been manufactured to allow acidizing of particular footage of well casing while sealing off the well casing both above and below the acidized section., Haliburton PPI packers have upper and lower packer elements which are spaced apart to allow acidizing to take place therebetween. Upper and lower exposed slips retain the packer in place against unwanted downward movement or against upward pressures within the well casing.
However, the packer element must often have increased sealing capabilities during increased well pressures. It is therefore desirable to have a booster piston which can further compress the packer elements during high pressures that are present within the well tubing.
Furthermore, it is desirable to have the packer that has an unloading gate valve that can be selectively opened or closed below the lower packer element to allow easy retrieval of the packer. It is also desirable to have enclosed slips for easy transportation and protection thereof.